1. Field of the Invention
The present invention relates to a disk clamper, and more particularly to an apparatus for activating a disk clamper by magnetic restoring force in which the disk clamper automatically moves upwardly or downwardly without interference with the optical disk cartridge and the disk clamper has a centering effect and a vibration-absorbing effect.
2. Description of the Related Art
A recordable optical disk drive generally includes a cartridge 13 (see FIG. 1 of the drawings) for protecting an optical disk. The cartridge 13 generally has a thickness of 8 mm and thus occupies a considerable space. The cartridge 13 may be interfered with by a disk clamper 12 when the former moves into or out of the optical disk drive. In order to 15 and thus the disk clamper 12 to a position above the lever 15 (FIG. 2). Thus, the disk clamper 12 is not contacted during the inward or outward movement of the cartridge 13 (FIG. 3). When the cartridge 13 approaches its innermost position, the lever 15 is contacted and thus urges the disk clamper 12 to move downwardly and thus xe2x80x9cclampsxe2x80x9d the optical disk, as shown in FIG. 4. Such a design requires many elements and the elastic member 14 has to be riveted to the disk clamper 12. Further, vertical movement of the lever 15 requires a considerable space. This is not advantageous to the design of optical disk drives.
It is a primary object of the invention to provide an apparatus for activating a disk clamper by magnetic restoring force to automatically move the disk clamper upwardly or downwardly without interference with the optical disk.
It is another object of the invention to provide an apparatus for activating a disk clamper by magnetic restoring force to reduce the space required for operation and the number of elements and thus simplify the assembly procedure.
It is a further object of the invention to provide an apparatus for activating a disk clamper by magnetic restoring force, in which the disk clamper may be automatically centered and vibrations thereof can be absorbed.
It is still another object of the present invention to provide an apparatus for activating a disk clamper by magnetic restoring force, in which friction between elements is avoided by means of interacting magnetic forces between magnetic members mounted in the disk clamper and other components.
The above objects are achieved by means of providing magnetic restoring force to replace the conventional design using elastic members and levers such that the magnetic restoring force between the magnetic members in the disk clamper and the magnetic casing of the optical disk drive and/or an annular magnet in the chucking plate may automatically lift or lower the disk clamper. Thus, an active force for activating the disk clamper is provided.
In accordance with one aspect of the invention, an apparatus for activating a disk clamper by magnetic restoring force is provided for an optical disk drive having a casing and a cartridge for carrying an optical disk along a path in the optical disk drive. The apparatus comprises:
a chucking plate adapted to be securely mounted below the casing, the casing being made of material which can be induced by a magnet such as ferric plate, the chucking plate including an opening;
a spindle motor mounted below the chucking plate and having a central axis;
a disk clamper slidably received in the opening of the chucking plate, the disk clamper including a magnet mounted therein, the disk clamper and the spindle motor being respectively located on two sides of the optical disk when the cartridge is inside the optical disk drive for securely clamping the optical disk together; and
an annular magnetic means mounted in the chucking plate and around the disk clamper,
whereby when the spindle motor moves upwardly, the disk clamper is moved downwardly to clamp the optical disk in the cartridge under action of magnetic force between the spindle motor and the magnet in the disk clamper, while the disk clamper is retained in position coaxial with the central axis of the spindle motor under action of casing, the magnet in the disk clamper, and the magnetic protrusion, thereby not causing an obstacle to inward movements of the cartridge into and out from the optical disk drive.
In accordance with a further aspect of the invention, an apparatus for activating a disk clamper by magnetic restoring force is provided for an optical disk drive having a casing and a cartridge for carrying an optical disk along a path in the optical disk drive. The improvement of the apparatus comprises:
a casing being made of material which can be induced by a magnet such as ferric plate;
a spindle motor mounted below the casing and having a central axis; and
a disk clamper including a magnet mounted therein and having a central axle coaxial with the central axis of the spindle motor, the disk clamper and the spindle motor being respectively located on two sides of the disc when the cartridge is inside the optical disk drive for securely clamping the optical disk together,
whereby when the spindle motor moves upwardly, the disk clamper is moved downwardly to clamp the optical disk in the cartridge under action of magnetic force between the spindle motor and the magnet in the disk clamper, and when the spindle motor moves downwardly, the disk clamper is moved upwardly under action of magnetic force between the magnetic casing and the magnet in the disk clamper, thereby not causing an obstacle to inward and outward movements of the cartridge into and out from the optical disk drive.
The magnetic elements are small and thus can be easily installed without occupying a considerable space. In addition, the space required for operation is relatively small, the number of elements is reduced, and the assembly procedure is simplified. Further, friction between elements is avoided as the active forces are magnetism.
Other objects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.